Seating system and method for making same

ABSTRACT

An improved seating system that includes a seat back assembly ( 10 ) that is fabricated to include a seat back ( 12 ) with first and second wall portions ( 14,16 ), and which may include an integrated reinforcement structure ( 18 ). The seating system is capable of either or both of withstanding without rupture at least about 11000 Newtons in the direction in which the seat back ( 12 ) faces in a plane, parallel to the longitudinal centerline of the vehicle or, upon rapid acceleration up to at least about 20 g, substantially no fragmentation of the seat back with at least a 30 kg mass placed behind the seat back.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of application Ser. No. 10/739,875filed on Dec. 18, 2003, now U.S. Pat. No. 6,997,515, which is acontinuation of application Ser. No. 10/265,977 filed on Oct. 7, 2002,now U.S. Pat. No. 6,688,700 which is a continuaton of application Ser.No. 09/766,792, filed on Jan. 22, 2001, now U.S. Pat. No. 6,491,346,which is a non-provisional of prior provisional application Ser. Nos.60/208,694 (filed Jun. 1, 2000) and 60/243,012 (filed Oct. 24, 2000),the teachings of all of which are hereby expressly incorporated byreference for all purposes. The present application claims the benefitof the priority of the filing dates of each of these prior applications.

TECHNICAL FIELD

The present invention relates to an improved seating system, and moreparticularly to an improved system for automotive vehicle seating.

BACKGROUND

There is an ever-growing need for improved seating systems in automotivevehicles. The surge in popularity of hatchbacks, sport utility vehiclesand minivans, has posed unique design challenges, in view of the needfor seating to be adjustable and in many instances to restrain cargocarried toward the rear of the vehicle. In light of the increasedconsumer usage of these vehicles for stowage and transport of cargoalong with passengers (particularly passengers in rear seats),manufacturers have turned their attention to improving the ability ofthe seating systems to withstand large loads.

One approach has been to develop improved systems for transmitting loadsto the seat tracks of vehicle seating assemblies. A growing number ofapplications, however, employ attachment of seating components directlyto the vehicle body in white for load distribution to the body in white.For the improved seat track technology to be viable in the latterapplications, it would require substantial modification, which isbelieved would unduly complicate the manufacturing procedures, requirethe development of expensive new processing techniques, or addsubstantial weight to the vehicles. Accordingly, there is a need for animproved, readily manufactured seating system that is capable of meetingvehicle manufacturer design criteria and government standards forvehicles, and which can be efficiently and conveniently adapted for usein a variety of applications including those involving seat track loaddistribution, body in white load distribution or both.

SUMMARY OF THE INVENTION

The needs in the art are met by the automotive vehicle seating system ofthe present invention, which includes a molded plastic seat back havinga first wall portion, an opposing second wall portion and one or morereinforcement structures disposed therebetween. An assembly is providedfor receiving the seat. Advantageously, the seating system upon rapidacceleration up to about 20 to about 30 g, no fragmentation of the seatback with at least a 36 kg mass placed behind the seat back. The systemis easy to manufacture and will not add substantial weight to thevehicle as compared with other commercial seating systems.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a seatback assembly;

FIG. 2 illustrates a sectional view of the seatback in FIG. 1;

FIGS. 3A–I illustrates examples of alternative seatback integratedreinforcement structure components and patterns;

FIGS. 4A and 4B are perspective views of illustrative seatbackassemblies;

FIG. 5 is a perspective view of one preferred hinge structure;

FIG. 6 is a perspective view of another preferred hinge structure;

FIGS. 7A–7D illustrate examples of alternative hinge configurations;

FIGS. 8A–D illustrates examples of alternative hinge bracketconfigurations;

FIG. 9 is a perspective view of a striker assembly;

FIGS. 9A–9F illustrate examples of seat back reinforcements;

FIG. 10 illustrates a sectional view of a preferred;

FIGS. 11A–11F illustrate examples of alternative striker assemblyconfigurations;

FIG. 12 illustrates a perspective view of another exemplary seat backstructure;

FIG. 13 is an elevation view of a seat back assembly;

FIG. 14 illustrates an example of an alternate pivotal mountingconfiguration;

FIG. 15 is a perspective view of an exemplary seatback assembly;

FIG. 16 is a perspective view of another exemplary seatback assembly;and

FIG. 17 is a perspective view of a seatback assembly illustratingassociated components.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, the present invention is premised upon thedevelopment of an improved automotive vehicle seat back assembly 10having a molded plastic seat back 12 including a first wall portion 14and an opposing second wall portion 16 (which wall portions may or maynot be integrally formed) and one or more integrated reinforcementstructures 18 disposed therebetween. A hinge assembly 20 is employed forpivotally anchoring the seat back 12 to an automotive vehicle. The hingeassembly 20 includes a receiving portion 22 for securing the seat backto said hinge assembly, and a mounting portion 24 for securing the hingeassembly to the vehicle. A retention mechanism 26 is employed formaintaining the seat back in a generally upright position. The hingeassembly 20, retention mechanism 26 or a combination of the twoeffectively define an assembly for attaching the seat back 12 to thevehicle and anchoring it to one or more body in white portions of thevehicle.

As used herein, and illustrated in FIG. 2, by reference to an exemplarmolded section 28, the phrase “wall stock thickness” or “wall thickness”shall refer to the dimension (T_(w)) between a first surface 30 and asecond surface 32 of a wall, such as first wall 34. Moreover, the phrase“part section thickness” or “section thickness” (T_(s)) shall refer tothe dimension between the first surface of the first wall and anoutwardly disposed surface 36 of a second wall 38, if cut by anintersecting plane.

The phrase “integrated reinforcement structure” shall refer to alocation where, as shown in FIG. 2 the first wall 34 and second wall 38of a molded component are joined, enlarged or reduced in wall thickness,section thickness, or otherwise configured to effectively create abeamed structural section for creating a locally modified bending momentor otherwise imparting additional rigidity, toughness or impactresistance to a seat back assembly.

By way of further reference to FIG. 2, various different structuralconfigurations are shown, one or more of which can be employed in thedesign of seat backs for the present invention. One such configurationincludes a tack-off 40, having a plurality of walls 42 (shown optionallyin contact with the wall 38) that are spaced apart to effectively definea beam structure. Another illustrative configuration includes a tack-off44 having a plurality of adjoining walls 46 in contact with each other.Yet another illustrative configuration includes a single wall rib 48,which can be formed, for instance, by employing one or a plurality ofmovable inserts in the tooling during forming. Still anotherconfiguration may include an enlarged rib 50 (i.e. having an enlargedportion on one or more of its sides) or some other like configuration.Another configuration includes a wall portion 52 that has a differentwall thickness relative to an adjoining wall portion.

As discussed previously, the present invention contemplates the use ofintegrated reinforcement structures for imparting additional rigidity,toughness or impact resistance to a seat back assembly, or otherwiselocally modifying the bending moment of a structure. While a variety ofstructures may be employed for this purpose, the most preferredstructures are selected from ribs, tack-offs or a combination thereof.

Advantageously, in one preferred embodiment in which the seat back isblow molded, integrated reinforcement structures 18 are integrallyformed during the molding process. By way of illustration, a seat backis fabricated by blow molding, pursuant to which a parison is placed ina cavity of a first tool adapted for defining the shape of a seat back.The parison is heated to a suitable temperature (e.g., for the preferredmaterials described hereinafter) from about 100° C. to about 400° C.,and more preferably about 225° C. to about 300° C. to induce plasticity.A gas is injected into the parison to cause expansion of the parisonwithin the tool cavity and the formation of generally opposing spacedapart first and second wall portions. At or after the expansion occursand while the material remains in its plastic state, the first oroptionally a second tool is brought into contact with one or both of thewalls and deforms each contacted wall in the direction of the opposingwall. In one embodiment, the opposing walls remain spaced from eachother. In a more preferred embodiment, the walls are brought intocontact with each other and remain in contact by this deformation step,thereby forming a tack-off. It will be appreciated that the effect offorming each tack off is to form a structure having wall portions thatproject away (e.g., as ribs) from the wall portions from which they areformed.

As illustrated in FIGS. 2 and 3, assuming an x-y-z orthogonal coordinatesystem, the section and wall profiles vary generally in at least oneaxis, e.g., in the z direction, to define individual integratedreinforcement structures. The section or wall profile might also vary ineither or both of the x direction (i.e. cross car) or y direction (i.e.generally vertical in the seat's upright position) for an individualintegrated reinforcement structure. In general the individual integratedreinforcement structures are made up of components that are verticallyoriented (i.e. in the y-direction), horizontally oriented (i.e. in thex-direction), of a predetermined geometry, or a combination of some orall of these. A grouping of a plurality of individual integratedreinforcement structures constitutes an “integrated reinforcementstructure pattern.” A seat back 12 may include one or more patterns 54.

FIG. 3 illustrates examples of various alternative predeterminedgeometric configurations for individual integrated reinforcementstructures 18. FIG. 3 also illustrates examples of various integratedreinforcement structure patterns 54. The individual integratedreinforcement structure 18, the integrated reinforcement structurepattern 54 may include one or a combination of any suitable letter,character, shape, or symbol. Examples of components of such structuresor patterns include, without limitation, the “C” shape, “D” shape, “H”shape, “I” shape, “J” shape, “L” shape, “M” shape, “N” shape, “O” shape,“S” shape, “T” shape, “U” shape, “V” shape, “W” shape, “X” shape, “Y”shape, “Z” shape, curves (e.g. sinusoidal curves), zig zags, “+” shape,or the like. Integrated reinforcement structure patterns 54 include aplurality of individual integrated reinforcement structures 18. As seenin FIGS. 3F and 3G, without limitation, the individual integratedreinforcement structure 18 may be a composite of multiple componentshapes. The patterns 54 may be random, as seen in FIGS. 3B and 3G, orrepetitious, as seen in FIG. 3A or 3E. One or more different type ofintegrated reinforcement structures 18 of the type illustrated in FIG. 2may be employed to define each pattern 54 used in a seat back 12.

For all applications, it should be appreciated that if a verticallyoriented integrated reinforcement structure requires openings to allowfor air flow during molding, the location of the openings is preferablystaggered to help reduce or eliminate hinge points. Further, where aplurality of vertically oriented integrated reinforcement structures isused in a pattern, the horizontal spacing (“x” in FIG. 3A) between eachindividual integrated reinforcement structure will vary from about 5 mmto about 100 mm and more preferably about 20 mm to about 50 mm.

One or more horizontally oriented integrated reinforcement structuresmight be incorporated in addition to or in lieu of vertical integratedreinforcement structures to help improve cross-car direction stiffnessin a seat back. When employed with vertically oriented integratedreinforcement structures, the horizontally oriented integratedreinforcement structures preferably are staggered between verticallyoriented integrated reinforcement structures or otherwise located tohelp reduce the likelihood they will serve as a hinge point. (See, e.g.,FIG. 3G). Horizontally oriented integrated reinforcement structures maybe added directly to existing vertically oriented integratedreinforcement structures (see, e.g., FIG. 3G and FIG. 3H). Thehorizontally oriented integrated reinforcement structures alternativelymay be incorporated into an overall pattern so that the integratedreinforcement structure is angled or is substantially perpendicular tothe horizontal bending diagonal plane.

The design and location of each integrated reinforcement structure 18and pattern 54 fabricated in the seat back 12 may be optimized for eachindividual application, taking into account some or all of the followingcriteria. For each application, the skilled artisan will appreciate thatthe specific integrated reinforcement structure employed is configuredto help minimize the bending or hinge effect caused by loads resultingfrom rapid deceleration or acceleration of a vehicle in the presence ofa passenger or cargo behind a seat (e.g., that which experienced by atop mounted center shoulder belt, top mounted child seat anchors, andluggage intrusion). For instance, in one preferred embodiment, theintegrated reinforcement structure and pattern selected generally is onethat will position a portion of the integrated reinforcement structurehaving a higher bending moment in a position generally perpendicular tothe torsional bending diagonal plane.

The use of integrated reinforcement structures is further illustrated inthe following discussion, by reference to two of the more commonlyexpected locations for integrated reinforcement structures, specificallyin the perimeter regions of a seat back and in the regions proximatehardware, such as seat belts, seat belt anchors, hinges, latchingcomponents or the like.

For a number of applications, it is particularly attractive toincorporate an integrated reinforcement structure around at least aportion of the perimeter 56 of the seat back 12 to help increasehorizontal stiffness, vertical stiffness, or both in the perimeterregions of the seat back. With illustrative reference to FIG. 3A, formost applications it is contemplated that an outboard edge 58 of theintegrated reinforcement structure 18 is at or within about 50 mm (andmore preferably about 15 mm) or less of an edge defining the perimeter56 of the seat back 12. With further reference to FIG. 2, the width(“w”) of any integrated reinforcement structure used in the perimeterregions of a seat back preferably ranges up to about 30 mm, and morepreferably it is about 4 to about 20 mm. Particularly for integratedreinforcement structures of the type depicted as tack-off 40 of FIG. 2,such dimension helps to minimize bending in the recessed valley portion60.

It is also preferable to form an integrated reinforcement structure inthe vicinity of any latch strikers or latch members. In someapplications, such as where the seat is intended to carry the load for acenter belt, or a child seat tether, it may be desirable to modify,further reinforce or eliminate the top perimeter horizontally orientedintegrated reinforcement structure to reduce the potential for hingeeffect stress concentrator in that vicinity. By reference to FIGS. 4Aand 4B (which show alternative hinge structures), in these applicationsand others, the bottom end 62 of a vertically oriented perimeterintegrated reinforcement structure 64 will be positioned below thehighest point 66 of a hinge assembly bracket 68 or other reinforcement70 securing the seat back to the vehicle. More preferably, the overlap(“O”) will range from about 25% to as high as about 100% of the verticallength (“L_(H)”) of any hinge or reinforcement. Further, the top end 72of such vertical perimeter integrated reinforcement structure will bespaced from (e.g., within about 10 to about 200 mm of) the top of theseat. Alternatively, a thicker part section thickness as available bythe use of structures 50 or 52 of FIGS. 1 and 2, may be incorporated atthe top or bottom of the seat back to help increase stiffness.

In instances where a center passenger shoulder belt system is employed,or a top child seat tether is employed, optionally, design criteria isemployed to help reduce the forward, downward and torsional or diagonalbending of the seat back that are caused by perimeter loads at oradjacent the shoulder belt or tether attachments. Preferably theintegrated reinforcement structures will provide good vertical stiffness(as this is the plane that is anticipated to endure the more severebending forces), as well as good torsional stiffness (responsive to thediagonal offset loads a passenger imparts to a shoulder belt system). Insuch instances, it is preferable to alternate geometries of theintegrated reinforcement structures either in a random or predeterminedpattern, or to maintain the integrated reinforcement structure width upto about 40 mm, and more preferably up to about 30 mm (e.g., about 5 toabout 30 mm).

The employment of vertically oriented integrated reinforcementstructures is particularly preferred in the load path for center beltloads and upper child seat tethers to help avoid vertical bending.Preferably, for these applications, the integrated reinforcementstructure width (W) will vary up to about 50 mm and more preferably willbe about 4 to about 40 mm, and still more preferably will be about 15 toabout 25 mm. The vertically oriented integrated reinforcement structurelength (L_(R)) will vary between about 70 to about 95% of the verticalseat back height, and more preferably about 80 to about 90%.

It will be appreciated that the above design criteria are preferred butare not intended as limiting. Depending upon the particularapplications, variations to the above may be made. Moreover, it shouldbe appreciated that forming an integrated reinforcement structure neednot occur in every application, and the need for and magnitude of suchgenerally will be directly proportional relationship to the size of theseat back. Thus, for example, a smaller folding seat may not require aperimeter integrated reinforcement structure or it may only require itin limited areas.

Referring by way of illustration to FIGS. 1 and 4–7 (without limitationas to the other configurations, such as ones excluding a verticallyoriented perimeter integrated reinforcement structure), for folding seatbacks, the hinge assembly 20 of the present invention is provided in anysuitable manner for assuring that the seat back remains anchored to thevehicle body in white in the event of a sudden or rapid acceleration,deceleration, or a large force is applied.

Though it is possible that locally reinforced structures integral withthe seat back may be employed in one preferred embodiment, it iscontemplated that one or more hinge assemblies 20 are secured to theseat back 12 after fabrication of the seat back. The hinge assemblies 20preferably include relatively tough and high strength to weightmaterials (such as plain carbon or alloy steels, or a comparable metal,composite or other material), and are configured for facilitatingcontrolled deformation for transmitting loads.

The hinge assembly 20 thus includes a bracket portion 74 adapted forreceiving or otherwise engaging the seat back 12, and a suitable pivotportion 76, that can be secured to a vehicle body or other mountingsurface, hingedly anchoring the overall seat back assembly 10. In onepreferred embodiment, the hinge assembly 20 (and any other anchoragesystem) is connected to an anchoring substrate, preferably the vehiclebody-in-white or an associated structure that has a breaking strengthequal to or greater than the breaking strength of the webbing of anyseat belt assembly installed as original equipment at that seatingposition. FIG. 1 illustrates one example of a manner for establishing apivot attachment, in which a cross bar 78 is mounted to the vehicle bodyin white and carries the pivot portion and associated bracket portion.In FIG. 14 it can be seen that another alternative is to employ no crossbar, instead having the bracket portion 80 adapted for mounting directly(or with an intermediate structure, such as seat track, pedestal, lowerlock/latch, or the like) to the vehicle body in white. In yet anotheralternative embodiment, as shown in FIG. 15, a frame 82 having a cutoutportion 84 is connected to define a seat halo assembly that may beconnected to the vehicle body-in-white.

The bracket portion 74 is adapted to receive the seat back in a nestingor mating type relationship, with the bracket portion acting as eitheror both of a male portion (e.g., if it is structured as a platereinforcement member 70, or another such insert member as in FIG. 4B) orfemale portion as generally shown in FIGS. 4A and 5–7. As illustrated inFIGS. 4–6, for the female portion bracket type includes a plurality ofadjoining walls for defining a well or a generally “U-shaped” channel(with or without at least one closed end) for receiving and holding theseat back 12. The average wall thickness of the bracket, assuming a highstrength metal such as steel, will range from about 1 to about 3 mm.

In one embodiment, the bracket portion is an elongate member, having alength of about 30 to about 300 mm, and a width of about 10 to about 75mm. (See e.g., FIGS. 5 and 6.) The well or wells can be disposedanywhere along the length of the hinge assembly (e.g., at one or both ofits ends, or at an intermediate location). The walls may be configuredin any suitable manner, with FIG. 5 illustrating two suchconfigurations. In FIG. 5, the walls include a first side wall portion86 and a second opposing side wall portion 88, both of which are aboutthe same length, and have an intermediate wall portion 90 bridging them.In FIG. 6, a first side wall portion 92 and a second side wall portion94 are joined with an intermediate portion 96. The first and second sideportions are arranged so that a distal end 98 of the second side portionextends beyond a distal end 100 of the first side portion 92. Theintermediate side portion 96 is such that it optionally includes asection terminating at an edge 102 that extends beyond the distal end100 of the first side portion 92 toward the distal end 98 of the secondside portion 94. The edge 102 may be any suitable configuration, e.g.,linear, curved, stepped or the like, as shown in the illustrations ofFIGS. 8A–8D. Further, though FIGS. 9A–9D illustrate a front to rearupward slope of the edge 102, the slope of the edge could be downward.

The hinge assembly is secured to the seat back 12 using any suitablejoining technique. It may be mechanically fastened (e.g., by screws orshoulder bolts), adhesively fastened, a combination thereof, orotherwise. In a particularly preferred embodiment, as illustrated inFIG. 7A, a fastener 104 is secured through the first wall portion 14 andsecond wall portion 16 of the seat back and the hinge bracket 74. InFIG. 7C a fastener 104 is fastened to a stud that is formed in the hingebracket 74 or otherwise placed between the opposing side wall portions.

As shown in FIG. 7B, in another embodiment, one possible bracketincludes a side wall portion configured with a projection 106 forcooperating with an integrated reinforcing structure 18 and establishingan interference connection, thereby reinforcing the attachment inresponse to forward directed longitudinal forces (as illustrated in FIG.7D). For instance, the bracket may be crimped into a tack off, orpreformed to include a projection that penetrates the volume defined bythe tack off, or otherwise grips an integrated reinforcement structure.

Referring to FIGS. 9A–9F, the hinge assembly optionally may be furtherreinforced by the placement of a supplemental reinforcing insert 108 ofsuitable geometry (such as triangular, square, polygonal, rounded orotherwise) between or outside of the walls of the seat back, preferablyin the vicinity of the bracket. Though it may be a steel (as with ahinge bracket), the reinforcing insert 108 preferably is made of arelatively tough and high strength to weight material, such as titanium,magnesium, aluminum, plastic, plastic composite, carbon fiber or thelike. The supplemental reinforcement may be hollow or solid, and it mayextend the entire span of the bracket or only a portion of it, or evenbeyond the bracket. By way of example, for split seats, the typicalvertical length of one such reinforcement may range up to about 300 mm,with a cross car width of about 10 to about 75 mm and a fore/aft depthof about 12 to about 37 mm.

It should be appreciated that the use of supplemental reinforcements isnot limited to the regions adjacent the hinge assembly, but may beanywhere within the assembly. In this regard, a relatively rigid member,such as a metal (e.g., steel), composite, unfoamed plastic, or foamedplastic (either prefoamed or foamed in situ) may be incorporated betweenwalls of a seat back wherever localized reinforcement is sought. Withoutlimitation, examples of suitable foams include polyurethanes, epoxies,styrenics, or the like. Softer foams may also be employed for noise andvibration absorption.

Generally, the hinge assembly 20 will result in a portion of the seatback 12 that is susceptible to function as a deformation site or stressconcentrator in the event of a sudden or rapid acceleration ordeceleration of the vehicle. As seen in FIG. 1, such anticipateddeformation site is placed toward the wall that will be forward facingwhen assembled in the vehicle. For instance, it may be located along theleading edge of the seat back for inducing a compressive load in thatregion.

As will be appreciated, the brackets described above are particularlyadvantageously used in foldable seat applications such as found in rearseats of hatchback vehicles sedans or coupes. However, they may also besuitably employed in free standing seating assemblies, in which casethey will be mounted to a pedestal or other structure associated with aseat track.

As discussed elsewhere herein, and referring now also to FIGS. 1, 10,and 11 the present systems may incorporate one or more retentionmechanisms 26 (e.g., latch assemblies) at any of a number of differentlocations on the seat assembly (e.g., along the seat sides, on the seatback, or along the top of the seat back), for affording releasable selflocking of the seat back to the vehicle relative to its hinge. It ispreferred that any such retention mechanism provide a sufficientcombination of high strength and good load distribution over thestructure to which it is attached and high strength. Preferably, theconfiguration is such that the seat is maintained in place by theretention mechanism in the event of a sudden or rapid acceleration,deceleration or other force, so that load on the seat back can betransferred as desired within the seat back.

Retention mechanism configurations may vary application to application.However, once engaged, for a forward-facing seat preferably suchmechanism preferably will not release or fail when a forwardlongitudinal force (Newtonss), equal to the product of 9.8 and 20 timesthe mass of the hinged or folding portion of the seat (kilograms), isapplied approximately through the center of gravity of the latched seatportion. Moreover, once engaged, the mechanism preferably also will notrelease or fail when subjected to an acceleration of about 20 g., in thelongitudinal direction opposite to the seat folding direction.

One preferred retention mechanism is a latch assembly 110, as shown inFIG. 10, which includes a conventional latch 112 having a retractablepawl, and a corresponding striker 114. Though illustrated with referenceto a striker secured to the seat back, either the striker or the latchmay be secured to the seat back, with appropriate configurations toavoid having it pull through the seat back 12.

Illustrative alternative configurations are disclosed in FIGS. 11A–F. Ineach instance the striker 114 includes at least one mounting portion 116for attaching to the seat back 12 (either adhesively, with suitablefasteners, or otherwise) and a projecting striker bar 118 (whichprojects through an aperature or slot in the seat back 12). The mountingportion 116 includes one or more flanges 120 for overlapping with andengaging the seat back 12 or an integrated reinforcement structure 18associated with it (e.g. FIG. 11F). The overlap preferably ranges fromabout 3 mm (and more preferably about 10 mm to about 150 mm). As shownin FIGS. 11C and 11D, in some embodiments a supplemental reinforcingplate 122 or like structure may also be employed.

All illustrated in FIGS. 11B and 11E, without limitation, shoulder bolts124 or other like structures may optionally be employed as desired forsecuring the retention mechanism 26 to the seat back 12.

It may be desirable to further reduce the potential for the retentionmechanism to create a hinge point, by locally reinforcing the seat backin or adjacent the region to which the latch member is secured. This canbe done in any suitable manner, for instance, by the incorporation ofone or more integrated reinforcement structures in that region or byincorporation of an additional or supplemental metal, plastic orcomposite reinforcement member within the seat back, about the entiretyor at least a portion of the perimeter of the seat back. For instance,FIG. 12 illustrates an L-shaped supplemental corner reinforcement 126,which is a relatively rigid member located between the opposing walls ofthe seat back. The supplemental reinforcement 126 can also be reorientedorthogonally about the z-axis relative to the position shown in FIG. 12.Of course, in such regions, integrated reinforcement structures may beemployed as desired to achieve such reinforcement. Typically, if thestriker bar 118 is located below about 20% of the height of the seatback, measured from the top of the seat back, then the supplementalreinforcement member is incorporated and positioned generally in theanticipated load path between a seat belt mounting point (if any) andthe striker bar 118.

It will be appreciated that the use of a supplemental reinforcementmember is not limited to the vicinity of the latch. One or moresupplemental reinforcement members may be used elsewhere in the seatback. For instance, a hybrid seat back having a rigid supplementalreinforcement member may be placed between or outside of the seat backwalls generally about the perimeter of the seat back.

With reference to FIG. 13 there is shown a typical split folding seatback assembly. The location of the retention mechanisms may be anywhereproximate the top or sides of the seat backs. Mustrated are alternativefirst, second and third respective locations 26A illustrating along aseat back side; 26B illustrating in one of the seat back corners; and26C illustrating along the top of the seat back.

Referring to FIG. 14, a seatback configuration is illustrated with apivotal mounting member. This configuration illustrates a seatback 12with an extending pivot member 128. The extending pivot member 128 isconfigured such that the seatback 12 may be pivotally mounted to abracket portion 80 thus negating the need for a cross bar 78.

As will be appreciated, proper material selection will permit efficientdesign and molding of optimal wall thicknesses, part section thicknessesor both, for achieving the desired performance without substantiallyincreasing vehicle weight or intruding into interior space availability.By way of example, it is desired for many applications that the maximumwall stock thickness will range up to about 6 mm or higher, morepreferably it will range from about 1.5 mm to about 4.0 mm, and stillmore preferably, it will range from about 2.5 mm to about 3.5 mm.Likewise, the maximum section thickness will range up to about 60 mm,more preferably it will range from about 20 mm to about 40 mm, and stillmore preferably it will range from about 25 to about 35 mm.

The materials selected for forming the walls of the seat backs of thepresent invention preferably exhibit an elastic modulus ranging fromabout 500 MPa to about 6000 Mpa, and more preferably about 1300 to about1500 Mpa, and still more preferably about 1700 to about 2500 MPA. Inapplications when the seat back is also to be used as a load bearingfloor, it is preferable to select a material toward the higher end ofthe ranges.

The preferred flexural modulus will be at least about 600 MPa, morepreferably it will range from about 200 to about 500 ksi (1300 to about3500 MPa), and still more preferably about 250 to about 350 ksi (1700 toabout 2500 MPa).

The preferred yield strength of the material ranges from about 20 toabout 200 Mpa. More preferably it will range from about 25 to about 70MPa and still more preferably about 35 to about 55 Mpa. Moreover, theductility (as measured by percent elongation) of the material preferablyranges from about 20% to about 150%, and more preferably it is at leastabout 30% and still more preferably, it is at least about 100%.

The material also will preferably exhibit attractive processingcharacteristics, such as a melt flow rate (230° C./3.8 kg-l; accordingto ASTM D1238) of about 0.300 to about 5.0 g/10 min to about 0.900 toabout 3 g/10 min; a softening point (according to ASTM D1525) of lessthan about 180° C., and more preferably about 90° C. to about 150° C.;linear-flow mold shrink (according to ASTM D 955) of about 0.076 mm/mm(0.003 in/in) about 0.203 mm/mm (0.008 in/in) and more preferably about0.152 mm/mm (0.006 in/in) to about 0.178 mm/mm (0.007 in/in); or acombination of these properties.

Accordingly, in one preferred embodiment, the seat back of the presentinvention preferably is made from a plastic material, and morepreferably a thermoplastic material. In a particularly preferredembodiment, the seat back is made from a high strength thermoplasticresin selected from styrenics, polyamides, polyolefins, polycarbonates,polyesters or mixtures thereof. Still more preferably they are selectedfrom the group consisting of acrylonitrile butadiene styrene,polycarbonate/acrylonitrile/butadiene styrene, polycarbonate,polyphenylene oxide/polystyrene, polybutylene terephthalate,polybutylene terephthalate/polycarbonate, polyamide (e.g., nylon),polyesters, polypropylene, polyethylene, and mixtures thereof.

Examples of preferred commercially available materials include PULSE®2200 BG and MAGNUM® 1150 EM, both available from The Dow ChemicalCompany.

The skilled artisan will recognize that the above teachings may bemodified in any of a number of ways yet still stay within the scope ofthe present invention. Among the many different options are thefollowing.

While the technology of the present invention has been illustrated inconnection with a blow molding fabrication process, it is not intendedto be limited to such process. Like results may be attainable using theteachings of the present invention in combination with other fabricationtechniques, including but not limited to injection molding, lost coreprocessing, rotoforming, compression molding (with or without decorativeor structural inserts), thermoforming, or the like. Preferably, whenblow molding, the processing temperature will range.

As will be appreciated from the above, preferred seating systems thatare optimized in accordance with the criteria outlined herein, and usingthe referenced materials, consistently should pass United States andEuropean government test standards for motor vehicles (e.g., asaddressed in FMVSS 207, FMVSS 210, FMVSS 225 (49 CFR 571.207, .210,.225) or ECE 17; all such standards being expressly incorporated byreference herein) as well as the requirements of automobile originalequipment manufacturers and their suppliers.

In one embodiment, the seating system (1) is capable of withstandingwithout rupture at least about 11000 Newtons in the direction in whichthe seat faces in a plane, parallel to the longitudinal centerline ofthe vehicle; (2) exhibits, upon rapid acceleration up to at least about20 g, substantially no fragmentation of the seat back with at least a 30kg mass placed behind the seat back; or (3) both (1) and (2).

More preferably, the seating system (1) is capable of withstandingwithout rupture at least about 13000 Newtons in the direction in whichthe seat faces in a plane, parallel to the longitudinal centerline ofthe vehicle; (2) exhibits, upon rapid acceleration of about 20 to about30 g, substantially no fragmentation of the seat back with at least a 36kg mass placed behind the seat back; or (3) both (1) and (2).

Though not intended to be limited thereby, in one embodiment, the seats,the anchorages, attachment hardware, and attachment bolts for thesystems of the present invention are capable of withstanding withoutcomplete rupture at least a 3000 pound force and more preferably a 5,000pound force. In one particularly preferred embodiment, the system iscapable of withstanding a force of at least about 13,000 N to about22,000 N generally in the direction in which the seat faces (to a pelvicbody block)in a plane parallel to the longitudinal centerline of thevehicle, with an initial force application angle of not less than about5 degrees or more than about 15 degrees above the horizontal. Still morepreferably, the system withstands such force even when applied at anonset rate of not more than about 133,000 N per second to about 222,000N per second, whereby the force is attained in not more than about 30seconds and is maintained for about 10 seconds.

In yet another embodiment, each seat assembly is capable of withstanding

-   (a) in any position to which the seat can be adjusted, a force    (Newtons) of 20 times the mass of the seat in kilograms multiplied    by 9.8 applied in a forward or rearward longitudinal direction; or-   (b) in its rearmost position, a force that produces a 373 Newton    meters moment about the seating reference point for each designated    seating position that the seat provides (as applied to an upper    cross-member of the seat back or the upper seat back, in a rearward    longitudinal direction for forward-facing seats).

In yet another highly preferred embodiment, the seatback of the presentinvention is incorporated into a seat assembly, and two 18 kg masses(e.g., cubes with an edge length of about 300 mm) are placed about 200mm from the seat back. Upon rapid acceleration to at least about 20 toabout 30 g, the seatback maintains the cargo disposed behind the seatback, with no visible fragmenting of the seat back or formation of sharpedges or corners.

Advantageously, in one additional preferred embodiment, the seat backsmade in accordance with the present invention are capable of exhibitinga set less than 6 mm after soaking for about 4 hours at about 82° C.with an applied load of about 244 kg/m² and a momentary load of about615 kg/m².

The stiffness, impact strength, and crack resistance of this seat backalso will greater than conventionally fabricated current blow moldedpolyethylene, filled polyethylene, polypropylene, or filledpolypropylene seat backs.

The present invention contemplates techniques and methods for theoptimization of one or more of material selection, wall thickness,section thickness, hinge design, and latch design, for realizing thedesired stiffness and strength to meet traditionally demanding loadrequirements in automotive vehicles occasioned of center mountedshoulder belt loads, child seat anchor loads, or cargo intrusion. Theskilled artisan will recognize, however, that from application toapplication, design requirements will vary, and therefore a reasonableamount of experimentation may be needed to adapt the various teachingsto the unique intended environment. By way of example, part size, seatbelt location, hinge points, latch locations, and split ratio may affectfinal design. It is believed that the use of conventional computer aidedengineering (CAE) techniques in combination with the present teachingswill yield satisfactory results, which can be improved as desired withconventional techniques for localized steel reinforcement (e.g., in highstress areas, such as hinge points, latch areas, seat belt mountingareas, and armrest support areas).

Thus, the present invention finds useful application in connection withany of a number of different types of seating systems, including but notlimited to, adjustable seats, fixed position seats, foldable seats,seats pivotal about an axis, including but not limited to hinged seats.The seats may be vehicle rear seats, vehicle front seats, jump seats orthe like. Moveable seats may be held in place by latches disposed in thecentral portion of the seating configuration (e.g., at the top), alongthe seat sides (anywhere from the top to the bottom), or elsewhere.Fixed seats may include no latch assembly nor any assembly. The seatingsystem may include one or more rear seats that fold downward to a largerstorage area, and which may require the seat back to act as load floor.The seat may be a split design (e.g., about 50/50, 60/40, 70/30 or thelike), or the seats may constitute a one piece design. In oneembodiment, the seat back is latched to either a structural packageshelf (top latches) or to the body in white (side outboard latches), andseat belt anchors or seat belt guidance system (as may be needed for acenter mounted belt) for the two outboard seats is not attached on theseat. (See FIG. 1).

A sliding lock pin might be incorporated between two folding seats. Thesliding pin can be unlocked to fold down one portion of the seat andself locking when the seat backs are both upright. Localizedreinforcement (e.g., steel reinforcement or plastic foam) for aspreading loads may be incorporated into potential stress concentrationlocations, such as hinge points, latch areas, seat belt anchoragelocations, child seat tether anchor locations, head rest attachments,armrest support areas, or the like.

In another embodiment, seat belt anchors or a seat belt guidance systemfor the center seat belt and/or child tether anchors are attached to theseat. Preferably, the top center seat belt mounting location is towardsthe middle of the seat back to help minimize the extent of cantilever,thereby helping to minimizing bending in response to a force.

Though it finds application in a variety of other environments (e.g.,rail transportation seating, air transportation seating, amusement parkrides, auditorium or stadium applications, or elsewhere), the presentinvention is particularly suitable for application in automotivevehicles of a number of different types, including but not limited topassenger cars (including sedans, coupes, station wagons, convertibles,or the like), multipurpose passenger vehicles (including sport utilityvehicles, sport activity vehicles, minivans, or the like), trucks, andbuses.

Systems of the present invention are not limited to seat backs, but mayalso include one or more additional components for a vehicle interiorsystem, particularly a seating system, such as seat belts, and seat beltanchorage components for transferring seat belt loads to the vehiclestructure, including, but not limited to, the attachment hardware, seatframes, seat pedestals, the vehicle structure itself, and other parts ofthe vehicle that help to prevent of the belt from the vehicle structure.The systems may optionally include supplemental inflatable restraintsystems, such as air bags. Other seating system components that arecontemplated as within the systems of the present invention include,without limitation, seat adjusters (power actuated and manual), lumbarsupports, child seats, child seat tether anchors, synthetic upholstery,natural upholstery (such as leather), seat warmers, seat coolers,headrests, integrated stereo components, arm rests, leg rests, cupholders, or the like. While in a preferred embodiment the seat beltincorporated into the system is a shoulder belt, and more preferably athree point harness, other seat belt types may also be used, such as lapbelts only, lap belts with a separate or detachable torso belt.

As will be appreciated, the present invention also affords considerabledesign and manufacture flexibility, including but not limited to theability to vary the configurations and contours of the respectiveopposing walls of a seat back. For instance, a first wall could bemoldably configured to provide a suitable lumbar support. An opposingwall (i.e., the rearward facing wall when the seat back is in itsupright position) could be configured to provide a relatively flatsurface for carrying loads. Optionally, the opposing wall could beconfigured with suitable component housings or cargo carrying implementssuch as troughs, tie down members, tonneau cover brackets, seat beltretractor housings, or the like.

EXAMPLE 1

Two seat back assemblies are fabricated for a sedan vehicle, such as theseat back assembly as shown generally in FIG. 15 having individualintegrated reinforcement structures 18 defining an integratedreinforcement structure pattern 54 and an upper edge latch (not shown).One is fabricated using blow molded PULSE® 2200 BG resin (from The DowChemical Company). The other one is fabricated using blow molded MAGNUM®1150 EM resin (from The Dow Chemical Company). A halo frame 82 carriesthe seat backs, which are hingedly connected along their bottom edge 130and latched along the top edge 132. As with Examples 2–4, the seat backincludes two child seat tether anchors 134, although other applicationsmay include no anchor, a single anchor or more than one anchor, upper orlower. The final seat back has an average wall thickness in the seatback of about 3 mm, and an average section thickness of about 25 mm.Both assemblies pass United States and European government teststandards for motor vehicles as addressed in FMVSS 207 (49 CFR 571.207),FMVSS 225 (49 CFR 571.225) and ECE 17, as well as the requirements ofautomobile original equipment manufacturers and their suppliers.

EXAMPLE 2

Two seat back assemblies are fabricated for a vehicle with a rear hatch,such as seat back assembly as shown generally in FIG. 1. One isfabricated using blow molded PULSE® 2200 BG resin (from The Dow ChemicalCompany). The other one is fabricated using blow molded MAGNUM® 1150 EMresin (from The Dow Chemical Company). The final assembly has an averagewall thickness in the seat back of about 3 mm, and an average sectionthickness of about 30 mm. Both assemblies pass United States andEuropean government test standards for motor vehicles as addressed inFMVSS 207 (49 CFR 571.207), FMVSS 225 (49 CFR 571.225) and ECE 17, aswell as the requirements of automobile original equipment manufacturersand their suppliers.

EXAMPLE 3

Two seat back assemblies are fabricated for a vehicle to be afree-standing seat assembly, such as assembly as shown generally in FIG.16 having individual integrated reinforcement structures 18 defining anintegrated reinforcement structure pattern 54. The seat backs aresecured to the vehicle body in white with a conventional lowerlock/latch 136 connected to a bracket 138. One is fabricated using blowmolded PULSE® 2200 BG resin (from The Dow Chemical Company). The otherone is fabricated using blow molded MAGNUM® (1150 EM resin (from The DowChemical Company). The final assembly has an average wall thickness inthe seat back of about 3 mm, and an average section thickness of about30 mm. Both assemblies pass United States and European government teststandards for motor vehicles as addressed in FMVSS 207 (49 CFR 571.207),FMVSS 225 (49 CFR 571.225) and ECE 17, as well as the requirements ofautomobile original equipment manufacturers and their suppliers.

EXAMPLE 4

Two seat back assemblies are fabricated for a vehicle to have a centershoulder belt such as seat back assembly as shown generally in FIG. 17having individual integrated reinforcement structures 18 defining anintegrated reinforcement structure pattern 54 and a latch (not shown).One is fabricated, using blow molded PULSE® 2200 BG resin (from The DowChemical Company). The other one is fabricated using blow molded MAGNUM®1150 EM resin (from The Dow Chemical Company). The seat back includes ahousing 140 on one of its walls (illustrated optionally on the rearwall), for a seat belt retractor 142. The final assembly has an averagewall thickness in the seat back of about 3 mm, and an average sectionthickness of about 30 mm. Both assemblies pass United States andEuropean government test standards for motor vehicles as addressed inFMVSS 207 (49 CFR 571.207), FMVSS 210 (49 CFR 571.210), FMVSS 225 (49CFR 571.225) and ECE 17, as well as the requirements of automobileoriginal equipment manufacturers and their suppliers.

The foregoing discussion discloses and describes merely exemplaryembodiments of the present invention. One skilled in the art willreadily recognize from such discussion and from the accompanyingdrawings and claims, that various changes, modifications and variationscan be made therein without departing from the spirit and scope of theinvention as defined in the following claims.

1. A seating assembly for an automotive vehicle, comprising: a plasticseat back having at least one wall portion having a forward wall portionand a rearward wall portion, the forward wall portion and rearward wallportion defining an interior open space between them; a tubular shapedreinforcement insert substantially enclosed by the forward wall portion,the rearward wall portion or a combination of both, wherein; i) thereinforcement insert extends about perimeter regions of the seat back;ii) the reinforcement insert intimately contacts a substantial portionof at least the forward wall portion or the rearward wall portion; andiii) the reinforcement insert is formed of a metal selected from steel,titanium, magnesium, aluminum or a combination thereof; and a pluralityof integrally molded plastic reinforcement structures extending acrossat least a portion of the at least one wall portion and forming a shapedpattern on the seat back; wherein the seat back is pivotal within theautomotive vehicle.
 2. A seating assembly as in claim 1 furthercomprising a hinge assembly securing the at least one wall portion tothe vehicle wherein the reinforcement insert is in the vicinity of thehinge bracket.
 3. A seating assembly as in claim 1 wherein thereinforcement insert is hollow.
 4. A seating assembly as in claim 1wherein said seating assembly is capable of withstanding, withoutrupture, at least about 13000 Newtons in a direction in which said seatfaces in a plane, parallel to the longitudinal centerline of saidvehicle, and exhibits, upon rapid acceleration up to about 20 to about30 g, no fragmentation of said seat back with at least a 30 kg massplaced behind said seat back.
 5. A seating assembly as in claim 1wherein the reinforcement insert is located between the forward wallportion and rearward wall portion.
 6. A seating assembly as in claim 1wherein the reinforcement insert is located within about 50 mm of anedge defining a perimeter of the seat back.
 7. A seating assembly for anautomotive vehicle, comprising: a plastic seat back having a forwardwall portion and a rearward wall portion with an interior open spacetherebetween wherein: i) the seat back is pivotal within the automotivevehicle; ii) the forward wall portion and the rearward wall portion bothinclude an internal and an external surface; and a reinforcement insertdisposed within a cavity defined in a surface of at least one of theforward wall portion or the rearward wall portion wherein; i) thereinforcement insert is formed of a metal selected from steel, titanium,magnesium, aluminum or a combination thereof; ii) the reinforcementinsert is located adjacent a peripheral edge of the seat back and iscoextensive with the edge of the seat back.
 8. A seating assembly as inclaim 7 wherein the forward wall portion, the rearward wall portion orboth substantially surround the insert.
 9. A seating assembly as inclaim 8 wherein the forward wall portion and the rearward wall portionare formed of a blow molded plastic or an injection molded plastic. 10.A seating assembly as in claim 8 wherein the forward wall portion andthe rearward wall portion or both contact a substantial portion of thereinforcement insert.
 11. A seating assembly as in claim 8 wherein thereinforcement insert is located within about 50 mm of an edge defining aperimeter of the seat back.
 12. A seating assembly as in claim 8 whereinthe forward wall portion and rearward wall portion are formed athermoplastic that includes a polycarbonate material, a styrenicmaterial, a polyester, a polyamide, a polyolefin or a combinationthereof.
 13. A seating assembly as in claim 7 further comprising a hingeassembly securing the forward and rearward portions to the vehiclewherein the reinforcement insert is in the vicinity of the hingebracket.
 14. A seating assembly as in claim 7 wherein the reinforcementinsert is hollow, has a rounded shape or both.
 15. A seating assembly asin claim 7 wherein said seating assembly is capable of withstanding,without rupture, at least about 13000 Newtons in a direction in whichsaid seat faces in a plane, parallel to the longitudinal centerline ofsaid vehicle, and exhibits, upon rapid acceleration up to about 20 toabout 30 g, no fragmentation of said seat back with at least a 30 kgmass placed behind said seat back.
 16. A seating assembly as in claim 7wherein at least one integrally molded plastic reinforcement extendsacross at least a portion of the forward wall portion, the rearward wallportion or both.
 17. A seating assembly for an automotive vehicle,comprising: a plastic seat back having a forward wall portion and arearward wall portion with an interior open space therebetween wherein:i) the seat back is pivotal within the automotive vehicle; ii) theforward wall portion and the rearward wall portion both include aninternal and an external surface; and iii) the seat back defines acavity within the external surface of at least one of the forward wallportion and the rearward wall portion; a reinforcement insert disposedwithin the cavity defined in the external surface wherein; i) thereinforcement insert is hollow and is formed of a metal selected fromsteel, titanium, magnesium, aluminum or a combination thereof; ii) thereinforcement insert is rounded in shape; iii) the reinforcement insertis located adjacent a peripheral edge of the seat back and iscoextensive with the edge of the seat back; and iv) the at least one ofthe forward wall portion and the rearward wall portion contact asubstantial portion of an outer surface of the reinforcement insert; andv) at least one integrally molded plastic reinforcement extends acrossat least a portion of the forward wall portion, the rearward wallportion or both.